Seems that I'm having a little success ... the Edge racer got sorted and now this flies !

Tried today to sort the motor .... cut into the fuselage and removed the unit.

As you can see here - the motor has this nice cosmetic bullet rear end, but only two tiny little air holes - which actually allow access to the grub screws locking the bell to the shaft ...

Even a day after the flight - there's that aroma of a cooked motor ...

Took it apart and windings etc. all look fine - no blacking or anything ...

The cone - not possible to separate it of as it holds the shaft ...

So I did what another guy did .... ground back and then drilled the holes larger .. but would you believe that cone is STEEL ! The shards immediately covered the magnets !! Devils job to clear that crap out !

So now it has two large cooling holes ...

Refiited all ... glued up again ...

Found that i needed to fair in the duct behind the EDF ... so a piece of 3mm depron hot glued to the shroud cover with a proud section that then slid into the duct ... sorted that.

Put it on the scale for a thrust test ... had 1kg thrust on a 1.4kg model ... not quite as good as first test but still good enough.

Still trying to find a better motor ... I want a 3000 - 3200kv motor 28mm diameter to fit a 5 blade 70mm EDF unit and suited to 5S. Can I find that ? Not on HK anyway ... I see a lot of 4S where people WANT to run 5S ..

I don't know how tight the money is, but Fan Jets USA has several 70mm motor/fan combos available, and they offer overseas shipping. I bought a few 64mm 3s and 4s combos from them and they didn't disappoint! They come balanced as well.

I don't know how tight the money is, but Fan Jets USA has several 70mm motor/fan combos available, and they offer overseas shipping. I bought a few 64mm 3s and 4s combos from them and they didn't disappoint! They come balanced as well.

Seems to run sweet enough ... no vibration or anything different.

Will look at site ... the only model I have to take the 5S is this one .... I could drop back to a 4S but then it means buying more bigger LiPo's than I have presently.

When you look at the design of an EDF unit - it seems cooling of motor is last thing on designers mind.
Here I have three problems .... 1) the rotor hub completely masks the front of the motor .... 2) the motor is inside a tube ..... 3) rear cone on the motor restricting even the small amount of air that can get through.

i don't know edf setups, but could the cone on the motor be a heat sink. its aero dynamic,located in the very best airflow space possible to cool the motor down and being made the way it is would draw heat away from the motors windings and bell housing and dispell it in the air flow. just seems logical they wouldn't block the motors cooling.

nigel,i hope your feeling better bud. stu

narrow is the place to land...wide is the space to crash....choose the narrow way!

i don't know edf setups, but could the cone on the motor be a heat sink. its aero dynamic,located in the very best airflow space possible to cool the motor down and being made the way it is would draw heat away from the motors windings and bell housing and dispell it in the air flow. just seems logical they wouldn't block the motors cooling.

nigel,i hope your feeling better bud. stu

Maybe ... but it sure gets hot ... my room stank of hot windings even after the short flight when I got it home ! All my other EDF motors have blunt rears and cooling slots in ... the 2836 that others pointed to - I've ordered is conventional as well.

I only bought the 2839 with the cone based on the reviews saying it produced good thrust on 4S - which turns out to be BS !

Anyway - I have another problem to solve : How to launch the F16 on my rails ... they sit right at the width that co-incides with my servo arms !
I just tried it again and I reckon if I'm careful I might get away with it ... The aileron arms / rods are clear ... the elevators are not - but slight move to side and the model sits ok ...

Last is the hook .. I don't want a permanent hook and because the previous owner glassed the front section of the air duct - I reckon to have the hook taped to the underside with its rear prong through hole in the duct ..

It's a big model ... 1.4kgs all up weight ... will need a good pull on the catapult ... so far I lay out for 5kgs ... maybe that'll be enough ?

It seems like a powerful enough setup on 4s, seeing how well it got up and away in your video. What I was referring to earlier about exhaust was the fan swept area to exhaust area ratio. I learned about this a little while back, and had loads of fun measuring my edf's and doing math again like a school boy, and then making an excel spreadsheet so I could just plug in the numbers. Here's a link to what I found:

It seems like a powerful enough setup on 4s, seeing how well it got up and away in your video. What I was referring to earlier about exhaust was the fan swept area to exhaust area ratio. I learned about this a little while back, and had loads of fun measuring my edf's and doing math again like a school boy, and then making an excel spreadsheet so I could just plug in the numbers. Here's a link to what I found:

Yep - know about the eflux / swept area and all that ... she's set at optimal on exhaust nozzle ...

BUT that video is 5S ... not 4S ...

When previous owner tried on 4S ... she would wallow around struggling to stay up ... and finally just stall out. The original fan and motor was same as I bought and fitted .. 2800kv + 6blade ... identical in fact. I expected to have better luck as I was not fitting retracts, removing items from it like various extras underwing, back end of fuselage etc. I was splitting the ailerons / elevators from the single servo + loads of rods / links to separate micro servos for each surface and then mix in the Tx .. I saved a lot of weight ... but still a 4S was just not enough.
The 5S was an experiment knowing the motor would not take it ... I expected a bit longer flight before trouble ... but still - it shows the model will fly on 5S and fly well ... Just need that 5S capable motor.

I did think about contacting Lanxian Model Co in China for their factory motor but given the Turnigy price ...

I'm still a little perplexed as to why your F-16 needs 5S. Is it the AUW of nearly 3# that is driving this requirement?

The factory model is powered by 5S .... I made mistake of following the German shop lead who sold it to my pal with 4S packs. He'd stripped out the gear to fit to his Multiplex EDF ... and I had the broken bits of the bare shell.
I copied the original installation of 2800kv motor and 6 blade 70mm plastic EDF. He gave me the two 4S packs he had ... the 4S 3000 Shop pack supplied and the 4S 3000 nanotech he'd bought extra.

Once set-up and tested - it was obvious why he'd never been able to fly it successfully ... the 4S was woefully short on thrust barely edging over 700gr on a 1.3kg machine ...

I then searched to identify the model as he couldn't remember the factory name ... which I then found to be the Lanxian F16 ....

Any chance you could open up the outlet nozzle a bit? I recall we talked about it before and the reduction in area from the FSA (fan swept area) to the nozzle area was about 73%. That's a big reduction and while it would probably work fine for a fast flying model with tons of surplus power I'm sure this one would benefit from an outlet closer to 60mm diameter.

Any chance you could open up the outlet nozzle a bit? I recall we talked about it before and the reduction in area from the FSA (fan swept area) to the nozzle area was about 73%. That's a big reduction and while it would probably work fine for a fast flying model with tons of surplus power I'm sure this one would benefit from an outlet closer to 60mm diameter.

I thought about that - but the nozzle is not thick enough to open out ... it's actually a nozzle of a Mutliplex Funjet 70mm ...

Only way to do it would be to cut of the nozzle and build another in say 3mm depron rolled to a tube.

I have the 3200kv motor on it's way now - so really it's a matter of open up the DF unit and swap the motor once it arrives. 5S and 3200 should make her go quite well !!

Congratulations on the re-maiden flight! I love that you can tell in the video how nervous you are. I would get like that all the time flying one of my more expensive models. It would take 20 mins just to shop shaking after the flight was over.

Take a look at the http://www.command.com/wps/portal/3M...=5924736&rt=r3 "3M Command strips and hooks." Maybe you could use that as a semi-permanent mount for your launching hook. They have them in different weight ratings and you could just pop it back off when you are done.

I'm still waiting the new motor ... Xmas has obviously slowed the delivery.

Hook for bungee ....... still not decided ... I'm looking to see if way to do a hook that can swing out of way ... like some of those bathroom coat hooks ! When not needed - a small bit of tape to fix out of way.

I'm a noob but here is a link that may help. I just bought mine this week. Look at both spec's and parts.... may help you.

Checkout bananahobby.com and search f16

Hi and welcome to the addicts !!

I appreciate the link - but I actually have link to factory and the original specs on my F16 ... Lanxian.

I'm trying to find a way to better power without over-powering stock motors etc. The F16 I was given has had extra strengthening added underneath in form of Glassfibre work ... weight increase is significant.

I have a 2800kv motor coming that takes up to 6S ... so hopefully this will cure my ills.

.....The F16 I was given has had extra strengthening added underneath in form of Glassfibre work ... weight increase is significant.

I have a 2800kv motor coming that takes up to 6S ... so hopefully this will cure my ills.

Nigel,
That sounds like the familiar 'slippery slope' of ever ballooning weight. Weight initially added to 'beef up' of airframe. Plane now overweight and underpowered. Purchase larger motor, larger battery and ESC to resolve power shortage. Weight now balloons massively. Plane may have enough power to fly but flies like a lead brick due to sky high wing loading.... High wing loading and fast stall speed make model very difficult to fly and so it crashes spectacularly, higher speed and added inertia guaranteeing total destruction

Nigel,
That sounds like the familiar 'slippery slope' of ever ballooning weight. Weight initially added to 'beef up' of airframe. Plane now overweight and underpowered. Purchase larger motor, larger battery and ESC to resolve power shortage. Weight now balloons massively. Plane may have enough power to fly but flies like a lead brick due to sky high wing loading.... High wing loading and fast stall speed make model very difficult to fly and so it crashes spectacularly, higher speed and added inertia guaranteeing total destruction

I hope I'm wrong.

Along those lines, the recent lipos have C ratings high enough to not require large cells sizes, as they had in the past. Weight is so critical on most of my EDFs, that I just live with short flight times and use a relatively small battery that meets the power requirement. With some of them, 4 minutes is plenty of excitement for me anyway. Of course some models require large cells for ballast, but we try to avoid that as much as possible. Most of the newer ARFs I come across spec much larger batteries than I would use on models of their relative sizes.

Nigel,
That sounds like the familiar 'slippery slope' of ever ballooning weight. Weight initially added to 'beef up' of airframe. Plane now overweight and underpowered. Purchase larger motor, larger battery and ESC to resolve power shortage. Weight now balloons massively. Plane may have enough power to fly but flies like a lead brick due to sky high wing loading.... High wing loading and fast stall speed make model very difficult to fly and so it crashes spectacularly, higher speed and added inertia guaranteeing total destruction

I hope I'm wrong.

If you watch the videos - she actually flies OK ... just not fast. When the motor cuts - she glides quite well surprisingly.
The problem is trying to get more out of the power set-up and burning out motors that supposedly are capable of taking 5S ...
I cannot carry a 6S as that's way too heavy ... so that means I'm back to 5S and finding a motor with high enough KV etc.